Final Year Project

Essential oils are used in a wide variety of consumer goods such as detergents, soaps, toilet products, cosmetics, pharmaceuticals, perfumes, confectionery food products, soft drinks, distilled alcoholic beverages (hard drinks) and insecticides. The world production and consumption of essential oils and perfumes are increasing very fast. Production technology is an essential element to improve the overall yield and quality of essential oil. The traditional technologies pertaining to essential oil processing are of great significance and are still being used in many parts of the globe. Water distillation, water and steam distillation, steam distillation, cohobation, maceration and enfleurage are the most traditional and commonly used methods. Maceration is adaptable when oil yield from distillation is poor. Distillation methods are good for powdered almonds, rose petals and rose blossoms, whereas solvent extraction is suitable for expensive, delicate and thermally unstable materials like jasmine, tuberose, and hyacinth. Water distillation is the most favored method of production of citronella oil from plant material. Sources of natural essential oil Essential oils are generally derived from one or more plant parts, such as flowers (e. orris) and gums or oleoresin exudations (e.g. balsam of Peru, Myroxylon balsamum, storax, myrrh, benzoin). Methods of Producing Essential Oils Regarding hydrodistillation, the essential oils industry has developed terminology to distinguish three types: water distillation; water and steam distillation; and direct steam distillation.

Biochemistry, 2023

Essential oils can be extracted using various methods. Process choice significantly impacts yield and quality, leading to the development of processes aiming for maximum essential oil (EO) yields in a chemical state close to their native structure. In this chapter, various extraction techniques, including conventional ones and their intensification, are discussed along with their respective pros and cons. Additionally, new eco-friendly extraction methods have been introduced to enhance the conventional production of essential oils. The most traditional, straightforward, and widely utilized extraction techniques are hydrodistillation and steam extraction. In actuality, steam extraction techniques are used to extract 93% of all essential oils. Other common extraction techniques include enfleurage (particularly used with roses), cold pressing (just for citrus peel), and organic solvent extraction. The low yield, loss of volatile chemicals, lengthy extraction durations, and hazardous solvent residues of these procedures are its drawbacks. Microwave-assisted extraction and supercritical fluid extraction are two of the latest essential oil extraction techniques that have received considerable interest.

The Canadian Journal of Chemical Engineering, 2009

Essential oils are volatile oils, generally odorous, which occur in certain plants or specified parts of plants, and are recovered by accepted procedures, such that the nature and composition of the product is, as nearly as practicable, unchanged by such procedures (ISO, 1968). The principal uses are as: flavouring agent, medicinal and aromatherapy application. Today, the essential oils are sought-after for innumerable applications starting from markers for plant identifications to bases for semi-synthesis of highly complex molecules. The extraction of highly delicate essential oils from plants remains a crucial step in all these applications. By using steam to mediate the iv Table of contents v List of figures ..vi List of tables ..vii Nomenclature viii Chapter 1: Introduction 1.1 Background of essential oils, rationale and motivation 15 1.2 Aims and Objectives 1.3 Format of the study Chapter 2: Literature review 2.1 History of Essential Oils 2.1.1 General history 2.1.2 History of Eucalyptus Essential Oils 2.2 The uniqueness of Essential Oils 2.3 Uses of Essential oils 24 2.3.1. Fragrant uses 25 2.3.2. Medicinal uses 27 2.4 Methods of production 2.5 Important Physical and Chemical properties of Essential Oils 7 2.6 Factors affecting the yield and quality of the Essential Oils 40 Chapter 3: Principles of Steam Extraction of Essential Oils 3.1 Preamble 42 3.2 Components of the Extraction Plant 43 3.3 Basic scientific principles involved in the process 47 3.4 Techniques of Extraction 48 Chapter 4: Experiments 4.1 Introduction 4.2 Materials and methods 4.1.1 Collection of the plant material 4.2.2 Treatment of the plant material 53 4.3 General description of equipment and procedure 4.3.1 Experimental and equipment description 4.3.2 Hazop analyses of the experimental equipment and procedure 4.4 Condensate isolation and characterization of the oils extracts 4.4.1 Isolation of the oil extracts from the steam condensation 60 4.4.2 Quantitative characterization of the Eucalyptus Essential Oils extracts 61 4.4.3 Qualitative characterization of the Eucalyptus Essential Oil extracts 4.5 Conclusion Chapter 5: Results and Discussions 69 5.1 Introduction 69 5.2 The quantitative analyses of the oil extracts 70 5.3 The qualitative analyses of the oil extracts 72 5.4 The mathematical modelling of the oil extraction process 5.5 Concluding remarks 90 8 Chapter 6: Conclusions and Recommendations 6.1 Achievement of objectives 91 6.2 Contribution of the study 6.3 Critical evaluation of the study 6.4 Recommendations for further research 93 References Appendix A: Experimental run data analyses 99 A.1 Quantitative analysis results A.2 Qualitative analysis results

Essential oils are a composite mixture of volatile compounds present in a very low concentration in plants. A variety of methods have been invented for extracting these oils from plants such as cc8 including distillation, steam distillation, solvent extraction; However, these methods have their own advantages as well as limitations. In order to overcome the disadvantages and limitations, recently, some new methods which are more efficient have been developed such as supercritical fluid extraction, Microwave Assisted extraction and ultrasounds. Such methods not only enhance the yield but also reduce extraction time. Thus, such methods improve quality of oil. This essay covers the recent trend of extracting the essential oils from plants using various methods

2016

Background: Pure essential oils are derived from various part of the plants. These essential oils have a very high commercial value due to its properties. They are widely used in the various fields of industries, such as perfumery industries and pharmaceuticals. The essential oils for are primarily used in the perfumery industry and have a very high commercial value due to its therapeutic properties. Objective: study the techniques available to extract the essential oils from different plant and study the efficiency and the selectivity for this techniques. Results: The essential oils of the plant are composed of heat-sensitive chemical compounds, the use of steam distillation and Microwave-assisted extraction (MAE) techniques would inevitably inflict thermal degradation to the natural fragrance. In this experimental work, solvent extraction method was employed due to its mild extracting condition and lower operating cost. Ethanol was used as the solvent due to its high availability ...

2011

Figure 1. Essences from floral unit which they were extracted, such as oil of clove. An oil is "essential" in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not form a distinctive category for any medical, pharmacological, or culinary purpose. Essential oils are generally extracted by distillation. Other processes include expression, or solvent extraction. They are used in perfumes, cosmetics, soaps and other products, for flavoring food and drink, and for adding scents to incense and household cleaning products. Various essential oils have been used medicinally at different periods in history. Medical application proposed by those who sell medicinal oils range from skin treatments to remedies for cancer, and often are based on nothing better than historical accounts of use of essential oils for these purposes.

Industrial Crops and Products, 2013

Altering the distillation times of economically important essential oils such as peppermint (Mentha × piperita L.), lemongrass (Cymbopogon flexuosus Steud.), and palmarosa (Cymbopogon martinii Roxb.) oils may allow producers to increase the production, engineer the composition, and decrease the energy required for distillation. Experiments were conducted to model essential oil yield and oil composition of peppermint, lemongrass, and palmarosa oils as a function of the length of the steam distillation time (DT). Maximum essential oil yields of peppermint, lemongrass, and palmarosa were achieved at a DT of 20 min; further increases in DT did not increase oil yields. In lemongrass and palmarosa experiments, DTs of 240 min led to 25-40% reductions in oil yield compared to yields at 20-160 min. This study demonstrated that DT can be used as a tool for obtaining essential oils with specific targeted composition from peppermint, lemongrass, and palmarosa. Secondly, the study found that the optimum length of the DT for maximum essential oil yields of peppermint, lemongrass, and palmarosa was much shorter than the time usually used by researchers and processors. Shorter DT may save producers and processors energy costs and other resources. This study also suggests that comparison of data on oil composition must take into consideration the length of the DT.

International Journal of Research, 2016

Perfume industries are growing in demand as the living standards are improving day by day. There is increasing demand for perfumes. They mask the body odor. Various methods such as solvent extraction, hydro distillation and enfleurag can be used for oil extraction. Distillation based recovery processes such as steam and vacuum distillation are preferred for the extraction of essential oils from plant materials. Other methods include solvent extraction, expression or enfleurage. The current review summarizes research on various methods for oil extraction and perfume formation from various raw materials.

A number of medicinal and aromatic plants contain essential oils; some are grown on large areas as high-value crops for commercial production of essential oils. Plant-derived essential oils are natural products with diverse applications in various industries such as in food and beverages, perfumery and cosmetics, in pharmaceutical products, in aromatherapy, and also as eco-friendly pesticides. The aroma, composition, and the bioactivity of the essential oils within single plant species may vary significantly, due to genetic and environmental factors, but may also depends on postharvest management and extraction procedure. The end users demand consistency in supply and quality. The specific chemical profile and aroma of the essential oil forms the basis for its utilization and price on the international markets. For most of the commercially grown essential oil crops, the conditions for essential oil extractions that would guarantee consistency of quality but also economics have been researched and identified. Steam and hydrodistillation have been traditionally used as economical and simple methods for extraction of the essential oil from a number of aromatic plants. Still there is no agreement in the literature regarding the optimal distillation time. Our research in the last five years have demonstrated that by varying the steam or hydro-distillation time, one could obtain oils with defined specific composition, opening the possibilities to produce unique essential oils from the same batch of biomass or seed. Furthermore, by manipulating the extraction time and conditions, one can obtain oils or oil fractions with differential bioactivity. The resulting products (essential oil fractions) could have diverse industrial, medical, or environmental applications. These findings could be used by industry to develop new products, to reduce energy inputs and oil losses, and speed up oil extraction. Our results clearly demonstrated that the conditions for oil extractions must be reported when the essential oil content and composition of a specific plant has been reported. This will facilitate comparisons of oil yield and composition. Herewith, we summarize the recent research on how steam or hydrodistillation time and conditions alters essential oil yield and composition from some of the most widely grown and utilized essential oil crops.

Molecules

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind’s diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products ...